Brassieres (commonly known as bras) are undergarments for covering, restraining, shaping, and elevating the wearer's breasts. Brassieres are designed for specific body types, fashions, and activities. Common brassiere styles include full-coverage, push-up, padded, demi cup, plunge, multi-way, strapless, racerback, backless, and front closure. Regardless of the styles and types, brassieres often contain cups with underwires for added effects of shaping, lifting, and supporting the breasts. In some instances, brassiere cups are integrally attached to garments, such as tank tops, shirts, dresses, or bathing suits.
Typically, the underwires in brassiere cups extend partially or entirely along the lower periphery of the cups and are positioned in a sleeve disposed about the lower periphery of each brassiere cup. In more modern brassieres, underwires are molded between layers of brassiere cup materials. Underwires are generally formed of thin lengths of a fairly rigid material, such as metal or polymeric material, having a rectangular or rounded cross-section. The rigidity of the underwire material is essential for lifting and holding the breasts in place. At the same time, the materials must be flexible enough to curve along the bottom contour of the breasts, which is a generally a widened U-shape.
While underwires have achieved widespread usage, certain disadvantages result from their use. During the use of a brassiere, or other supporting garments containing underwires, the underwires apply pressure to the wearer along the lower periphery of the brassiere cups. Notably, the ends or tips of the underwires create the greatest pressure on the wearer. Such pressure points are located at areas on both sides of the breasts proximate the wearer's armpits and areas in between the cleavage portion of the breasts. The pressure results in rubbing or pinching of the skin—rendering prolonged use of the brassiere uncomfortable or even painful. In a more serious case, the underwire tips could tear through the brassiere materials and partially expose the underwire as a result. If the exposed underwire tips are hard or sharp, they could scrape or puncture the clothing or skin of the wearer. Even if no such damages occur, the exposed underwire could cause skin irritation to some wearers due to an allergic reaction, especially when the underwire is made of metal.
Furthermore, the discomfort or pain accompanying the use of underwires in brassieres often causes the wearer's movement to be restricted. In fact, some wearers preemptively limit their movements in order to lower their level of discomfort or chances of getting injured. This defeats the purpose of wearing a brassiere, because brassieres replaced corsets as a means to free women from constricting garments.
A common practice for alleviating discomfort from brassiere underwires is to provide a cushion along the entire length of the underwire. Such cushions are often made of a soft foam, cotton, or layers of fabric. Although this solution helps to reduce the overall pressure, it does not effectively balance the uneven pressure created by the underwire tips. Moreover, the bulkiness of the cushion creates a space between the wearer's breasts and the brassiere—rendering the brassiere more prone to being displaced with movements of the wearer. The cushions may also cause brassiere to appear heavier and bulkier, which may interfere with fashionable outer garments. Therefore, such wearability problems are undesirable, both from practical and aesthetic perspectives.
Another solution to the problem accompanying the use of underwires is in a form of underwire end protectors. For example, a cushion tip made of a relatively soft material, such as plastic, can be attached at each end of the underwire. However, this solution too encounters problems. Since the end protectors are softer and more fragile than the underwire, there comes a point where the end protector breaks. This occurs when the brassiere is subjected to repeated use and wear created by the movement of the wearer. When the end protector reaches its stress threshold, it breaks and exposes a portion of the metal underwire. Some manufacturers have tried to solve this problem by completely encapsulating the underwire with more material such as rubber or foam. Again, the added materials cause displacement of the brassieres or undesirable bulkiness, resulting in wearability problems.
There is therefore a need for underwire brassiere cups that overcomes some or all of the previously delineated drawbacks of prior underwire brassieres. Particularly, there is a need for underwire brassiere cups that minimize wearability problems and painful pressure points on the body of the wearer, while also providing support and rigidity to the wearer.